United Continental (UAL) needs no introduction — it’s one of the largest air carriers in the world with north of $35 billion in annual revenue. It and other airline stocks had big runs into 2015 as earnings boomed.

Thanks to industry consolidation, competition has declined meaningfully (today, just four carriers control 90% of the market), allowing prices to remain firm for tickets and extras like bags, drinks and the like.

That said, profits began to sag, which took the stocks down for about 18 months, but now the tide has turned for UAL for a couple of reasons.

First and foremost, the stock is cheap, trading at just 11 times next year’s earnings, and the company is throwing off a ton of cash.

Free cash flow has totaled $2.6 billion in the first nine months of the year; the next three years is expected see free cash flow north of $9 billion, compared to a current market cap of $21 billion!

Second, the company isn’t resting on its laurels, announcing plenty of efficiency initiatives that could lead to another few billion dollars of profit in the years ahead.

All of that is probably a big reason why Berkshire Hathaway (BRK.A) just took a stake in UAL (along with other big players). Analysts see earnings falling to $6.26 per share next year, though that could prove conservative if the economy picks up steam.

It’s obviously not a major growth story, but with Buffett giving the thumbs up to the stock, we think UAL could see surprising upside, especially as transportation stocks have taken flight.

UAL peaked at $75 in January 2015 and fell as low as $37 during the post-Brexit panic in June of this year.

But the stock has been strong since — UAL trended higher during the past few months along its 50-day line, reaching the upper $50s before the election.

And it’s taken off during the past two weeks, first on the boom in transport stocks, and then on the Berkshire news. We think it will head higher over time, but believe it’s best to buy on dips of a few points.